Australia welcomes summer with weather extremes

Australia's first day of summer kicks off with one side of the country sweltering and another shivering, with extreme weather ushering in a change of seasons.

Today Perth is heading for a maximum temperature of 37 degrees, putting the city's hottest December 1 record of 37.4 degrees recorded in 1979 within sight.

In stark contrast, the mercury in Melbourne is forecast to climb to only 16 degrees, but that could turn out to be even cooler, with a chance the city's record summer low from 1987 of 15.5 degrees being broken.

READ MORE: Fire warnings issued as Australia braces for sweltering summer

Two powerful but contrasting weather patterns are behind this bizarre start of summer, reports weather channel Weatherzone.

Over in Western Australia, an often-seen trough is moving down the coast, pulling hot air from the state's interior to Perth and south-west regions.

The north-west of the WA is also forecast for scorching conditions over the next two day.

The Bureau of Meteorology has issued a severe heatwave warning for the Kimberley region.

Meanwhile, following an unusually chilly late spring, the wintry conditions in south-eastern Australia are forecast to linger into early summer.

The frigid weather in the Victorian Alps and Tasmanian Highlands has brought steady snowfalls, and they're likely to continue today.

Melbourne residents will be keeping their winter woollies handy, with thick cloud and showers, making it feel more like winter's first day than the opening of summer.

Looking ahead, Perth can expect some relief from the heat when the mercury falls to a maximum of 28 degrees tomorrow.

For Melbourne, warmer conditions should arrive by Wednesday, with a top of 27 degrees expected.

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